Falcatifolium

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Falcatifolium
Systematics
Department : Vascular plants (tracheophyta)
Subdivision : Seed plants (Spermatophytina)
Class : Coniferopsida
Order : Conifers (Coniferales)
Family : Stonecaceae (Podocarpaceae)
Genre : Falcatifolium
Scientific name
Falcatifolium
de foliage.

Falcatifolium is a genus of plants inthe stone slab family (Podocarpaceae). The natural range of the five or six species is on some islands, such as Indonesia, the Moluccas, the Philippines and Borneo and New Caledonia.

description

Vegetative characteristics

Falcatifolium species are evergreen shrubs or trees . Both the bark and the leaves contain resin. The bark is thin, fibrous, has scattered cork pores and can flake off. The branching in monopodial trees takes place in false whorls and is irregular in shrubs. Leafy branches end in loose buds formed by narrow, triangular scale leaves.

The wood is soft, light, fragrant and light brown and shows only minor differences between heartwood and sapwood . It is finely and evenly grained, growth rings are only indistinctly formed. Resin channels are missing, but individual resin cells are formed.

The leaves are bifold, a distinction is made between scale leaves and deciduous leaves. The scale leaves grow more or less pressed on the main shoots and cone-bearing shoots. The leaves grow more or less in two rows, they are flattened on both sides, so have a left and right side, and obliquely lanceolate-sickle-shaped. The leaves are single-nerved, significantly larger than the scale leaves, but very different in size. They form on both leaf surfaces stomata .

Generative characteristics

Falcatifolium species are dioeciously separated sexes ( diocesan ).

The pollen pins are cylindrical to kittens shaped . They usually grow individually less often in groups, axillary on scaly stems. The microsporophylls are small, triangular or pointed and show two round pollen sacs that contain pollen with two air chambers .

The seed cones grow individually, laterally or, more rarely, terminally on scaly stems. The seed cones consist of eight to twelve spirally arranged cover scales, which swell, become fleshy and turn red and together with the cone axis form an irregularly shaped “podocarpium”. A fertile seed scale grows near the tip of the podocarpium , which carries the single ovule on the adaxial side. The wingless seeds are egg-shaped, but more or less flattened and show two lateral ridges. They stand upright obliquely to the axis of the podocarpium and are surrounded at the base by the swollen epimatium, which is formed from one or two swollen seed scales.

The basic chromosome number is x = 10.

Systematics and distribution

Taxonomy

The genus Falcatifolium was established in 1969 by David John de Laubenfels in Journal of the Arnold Arboretum , Volume 50, page 308. Type species is Falcatifolium falciforme (Parl.) De Laub.

External system

The genus Falcatifolium belongs to the family Podocarpaceae within the order Coniferales . Species that were previously assigned to the resin disks ( Dacrydium ) were placed in the new genus Falcatifolium . The species of the genus Falcatifolium differ from those of the genus Dacrydium by the position of the cones, the shape of the epimatium and the different shape of the leaves. However, genetic studies show that the species of the genera Falcatifolium and Dacrydium are closely related, more closely than the genera Halocarpus , Lagarostrobos , Lepidothamnus and Manoao, which were later separated from the resin disks .

Species and their distribution

The distribution area of ​​the Falcatifolium species is in Melanesia , Borneo , Sulawesi , the Philippines , the Moluccas , New Guinea and New Caledonia .

The species of the genus Falcatifolium are closely related to each other, they differ mainly in the size and shape of the leaves. Aljos Farjon 2010 distinguishes the following six types:

  • Falcatifolium angustum de foliage. forms shrubs or trees up to 20 meters high. The leaves of young specimens are narrowly linear-lanceolate, up to 7 centimeters long and 1.2 to 1.5 centimeters wide, leaves of adult trees are usually longer than 1 centimeter. The species is endangered. It was first described in 1969. There are only two known sites on the Sarawak coast.
  • Falcatifolium falciforme (Parl.) De Laub. forms shrubs or trees up to 20 meters high. The leaves of young specimens are curved sickle-shaped or linear-sickle-shaped, 10 to 12 centimeters long and 10 to 12 millimeters wide. The leaves of fully grown shrubs or trees are 3 sickle-shaped or S-shaped, from 1.5 usually 2 to 9 millimeters wide, pointed or piercing. The podocarpium is shorter than 12 millimeters when ripe and has a diameter less than 6 millimeters. The species is potentially endangered. It occurs on the island of Lingga and in Borneo .
  • Falcatifolium gruezoi de foliage. forms shrubs or trees up to 20 meters high. The leaves are pink to purple when they shoot. The leaves of young specimens are sickle-shaped or linear-sickle-shaped and with up to 7.5 centimeters, and significantly longer than the approximately 4 centimeters long leaves of adult specimens, which are usually sickle-shaped at least near the base and rarely S-shaped. The pollen cones are 5 to 6 inches long. The species is potentially endangered. It comes from the Philippines (only in Luzon : Tayabas, Nueva Ecija; Mindoro ; Panay ; Mindanao : Davao, Surigao), on Celebes only in Manado (Poso, Gorontalo, Palu) and on the island of Obi ,which belongs to the Moluccas.
  • Falcatifolium papuanum de foliage. forms shrubs or trees up to 20 meters high. The leaves are whitish green to yellowish green or glaucous when they shoot. The leaves of young specimens are sickle-shaped or linear-sickle-shaped, and only slightly larger than the approximately 3 centimeter long leaves of adult specimens, which are usually sickle-shaped at least near the base and rarely S-shaped. The pollen cones are 0.5 to 1.3 inches long. The species is not endangered. It thrives in moist mountain forests at altitudes of 1500 to 2400 meters in New Guinea .
  • Falcatifolium sleumeri de foliage. & Silba forms low shrubs. Adult shrubs have leaves 0.6 to 1 centimeter long and 1.8 to 2 millimeters wide. The species is only known from one location in New Guinea and is considered to be potentially endangered. This endemic occurs only on Mt. Nettoti on the Vogelkop Peninsula in Irian Jaya in western New Guinea. In 19961 a herbarium was collected from a sterile specimen, which is the basis of the first description from 1988. No further material was collected that does not belong to Falcatifolium papuanum , since this only herbarium alsofits Falcatifolium papuanum , it is assumed that Falcatifolium sleumeri is a synonym of Falcatifolium papuanum .
  • Falcatifolium taxoides (Brongn. & Gris) de Laub. forms shrubs or trees up to 22 meters high. The leaves of young specimens are almost linear, 1 to 2 inches long and about 1.5 inches wide. The leaves of fully grown trees are 3 to 6 millimeters wide and have a blunt, more rarely a pointed tip. The podocarpium is 20 millimeters long and 8 millimeters in diameter when ripe. The species is not endangered. It thrives at altitudes of mostly 800 to 1200 (0 to 1400) meters in New Caledonia .

In 2009, James Eckenwalder sees Falcatifolium sleumeri only as a synonym for Falcatifolium papuanum . He gives the following distinguishing features for the remaining five species, whereby the Podocarpium is only decisive for differentiating between Falcatifolium papuanum and Falcatifolium taxoides and is not known for two species.

  • Falcatifolium angustum : The leaves are 2 to 4 centimeters long and up to 2.5 millimeters wide, the pollen cones are shorter than 1.5 centimeters, the podocarpium is unknown.
  • Falcatifolium falciforme : The leaves are at least 4 centimeters long and at least 6 millimeters wide, the pollen cones are 2.5 centimeters long or longer, the podocarpium is 3.5 to 5.5 millimeters long.
  • Falcatifolium gruezoi : The leaves are 2 to 4 centimeters long and up to 2.5 millimeters wide, the pollen cones are shorter than 1.5 centimeters, the podocarpium is not known.
  • Falcatifolium papuanum : The leaves are up to 2 centimeters long and 2.5 to 4 millimeters wide, the pollen cones are shorter than 1.5 centimeters and the podocarpium is longer than 5.5 millimeters.
  • Falcatifolium taxoides : The leaves are up to 2 centimeters long and 2.5 to 4 millimeters wide, the pollen cones are 1.5 to 2.5 centimeters long and the podocarpium is 3.5 to 5.5 millimeters long.

Fossil Finds

There are only a few fossil finds, finds from the Eocene of Southeast Australia are around 45 million years old. The separation from the other genres must have taken place beforehand. Finds with a similar leaf shape but a different surface structure are known from the Eocene and the more recent Oligocene of Tasmania and are assigned to a separate genus Sigmaphyllum .

use

The species in the genus are rarely cultivated, and there are no known cultivars . The wood of Falcatifolium falciforme and Falcatifolium papuanum is used economically together with the wood of other representatives of the stone slab family.

swell

literature

  • Aljos Farjon: A Handbook of the World's Conifers . tape 1 . Brill, Leiden-Boston 2010, ISBN 978-90-04-17718-5 , pp. 363, 365 and 367 .
  • James E. Eckenwalder: Conifers of the World. The Complete Reference . Timber Press, Portland, OR / London 2009, ISBN 978-0-88192-974-4 , pp. 259, 260 .

Individual evidence

  1. ↑ a b c d e f g Christopher J. Earle: Falcatifolium. In: The Gymnosperm Database. www.conifers.org, January 17, 2020, accessed on March 29, 2020 (English).
  2. ↑ a b c d e f g h i j k l m Aljos Farjon: A Handbook of the World's Conifers. Volume 1, p. 363
  3. ↑ a b c d e f g h i j James E. Eckenwalder: Conifers of the World , pp. 259–260
  4. ↑ Falcatifolium at Tropicos.org. Missouri Botanical Garden, St. Louis, accessed March 29, 2020.
  5. ↑ falcatifolium angustum in the Red List of Threatened Species of the IUCN 2013. Posted by: Aljos Farjon, 2011. Accessed March 29, 2020th
  6. ↑ falcatifolium falciforme in the Red List of Threatened Species of the IUCN 2013. Posted by: A. Farjon Farjon, G. Carter, 2010. Accessed March 29, 2020th
  7. ↑ Falcatifolium gruezoi in the Red List of Threatened Species of the IUCN 2013. Posted by: P. Thomas, 2012. Retrieved on March 29, 2020.
  8. ↑ falcatifolium papuanum in the endangered Red List species the IUCN 2013. Posted by: A. Farjon, 2011. Accessed March 29, 2020th
  9. ↑ a b falcatifolium sleumeri in the endangered Red List species the IUCN 2013. Posted by: A. Farjon, 2011. Accessed March 29, 2020th
  10. ↑ Falcatifolium taxoides in the Red List of Threatened Species of the IUCN 2013. Posted by: P. Thomas, 2010. Retrieved on March 29, 2020.
  11. ^ Aljos Farjon: A Handbook of the World's Conifers. Volume 1, p. 365
  12. ^ Aljos Farjon: A Handbook of the World's Conifers. Volume 1, p. 367

further reading

  • Aljos Farjon, Denis Filer: An Atlas of the World's Conifers: An Analysis of their Distribution, Biogeography, Diversity and Conservation Status . BRILL, 2013, ISBN 978-90-04-21181-0 , pp. 524 pages ( Falcatifolium on pp. 320-322 in the Google book search).

Web links